Bathtub



FIG. 1 is a perspective view of a bathtub, showing my design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a right side elevational view thereof, the left side being a mirror image of the right side shown; and

FIG. 5 is a rear elevational view thereof. 

The ornamental design for a bathtub, as shown and described. 